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Proton-K

The Proton-K, also designated Proton 8K82K after its GRAU index, 8K82K, was a Russian, previously Soviet, carrier rocket derived from the earlier Proton. It was built by Khrunichev, and launched from sites 81 and 200 at the Baikonur Cosmodrome in Kazakhstan.

The maiden flight on 10 March 1967 carried a Soyuz 7K-L1 as part of the Zond program. During the so-called " Moon Race" these Proton/Soyuz/Zond flights consisted of several uncrewed test flights of Soyuz spacecraft to highly elliptical or circumlunar orbits with the unrealized aim of landing Soviet cosmonauts on the Moon.

It was retired from service in favour of the modernised Proton-M, making its 311th and final launch on 30 March 2012.